The pipeline
<p:declare-step xmlns:c="http://www.w3.org/ns/xproc-step" xmlns:p="http://www.w3.org/ns/xproc" version="3.0">
<p:output port="result"/>
<p:archive>
<p:with-input port="source">
<p:inline document-properties="map{'base-uri' : 'http://test/one.xml'}">
<doc-a/>
</p:inline>
</p:with-input>
</p:archive>
<p:archive parameters="map{'command' : 'update'}">
<p:with-input port="source">
<p:inline document-properties="map{'base-uri' : 'http://test/one.xml'}">
<doc-new/>
</p:inline>
<p:inline document-properties="map{'base-uri' : 'http://test/two.xml'}">
<doc-b/>
</p:inline>
</p:with-input>
<p:with-input port="archive" pipe="result"/>
</p:archive>
<p:unarchive relative-to="folder"/>
<p:wrap-sequence wrapper="wrapper"/>
</p:declare-step>
Schematron validation
<s:schema xmlns="http://www.w3.org/1999/xhtml" xmlns:s="http://purl.oclc.org/dsdl/schematron" queryBinding="xslt2">
<s:pattern>
<s:rule context="/">
<s:assert test="wrapper">Root element is not wrapper</s:assert>
<s:assert test="count(wrapper/*)=2">Wrapper should only have two child elements.</s:assert>
<s:assert test="wrapper/doc-new">There is no child 'doc-new' in wrapper.</s:assert>
<s:assert test="wrapper/doc-b">There is no child 'doc-b' in wrapper.</s:assert>
</s:rule>
</s:pattern>
</s:schema>
